Seed trench depth detection systems

ABSTRACT

A row unit downforce system including: a downforce actuator in operational communication with the row unit and constructed and arranged to apply supplemental downforce to the row unit and opening disks; a monitoring system comprising at least one furrow depth sensor constructed and arranged to generate furrow depth values; and a control system module, wherein the control system module is constructed and arranged to generate actuator command signals in response to the furrow depth values.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of application Ser. No. 16/190,101,filed 13 Nov. 2018, which is a continuation of PCT Application No.PCT/US2017/032456, filed 12 May 2017, which claims priority to U.S.Provisional Application Nos. 62/336,069, filed 13 May 2016; 62/425,978,filed 23 Nov. 2016; and 62/465,134, filed 28 Feb. 2017, the disclosuresof all of these applications are incorporated herein by reference.

BACKGROUND

It is well known that good seed-to-soil contact within the seed trenchis a critical factor in uniform seed emergence and high yields. Whileconducting spot checks of the seed trench may help to provide someassurances that these critical factors are being achieved, such spotchecks will only identify the conditions at the specific location beingchecked. Accordingly, there is a need for a system that will verify thatgood seed-to-soil contact is being achieved during planting operationsand to enable automatic or remote adjustment of the planter whileon-the-go.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevation view of an embodiment of a row unit of anagricultural planter.

FIG. 2 illustrates an embodiment of a trench closing sensor and areference sensor disposed on a planter row unit.

FIG. 3 is an embodiment of seed firmer adapted to function as trenchclosing sensor showing the drag wire coupled to an instrument disposedin the body of the seed firmer.

FIG. 4 illustrates an embodiment of a trench closing sensor utilizing apressure transducer coupled to the rearward end of the drag wire.

FIG. 5 illustrates an embodiment of a trench closing sensor withvertically stacked drag wires.

FIG. 5A illustrates an alternative embodiment to that of FIG. 5 byincluding conductive tips at the end of the drag wires.

FIG. 6 is an enlarged side elevation view of an embodiment of areference sensor.

FIG. 7 is a rear elevation view of the reference sensor of FIG. 6 .

FIG. 8 is a diagram of a system for implementing operational control ofthe closing wheel assembly and packer wheel assembly based on signalsgenerated by the trench closing assembly.

FIG. 9 is a flow chart illustrating an embodiment for implementingoperational control and operator feedback based on the references sensorand trench closing sensor.

FIG. 10 illustrates an embodiment of a trench closing sensor and sensorsystem disposed on a closing system.

FIG. 11 illustrates an embodiment of a trench closing sensor and anangular sensor disposed on a closing system.

FIG. 12 is an embodiment of seed firmer adapted to function as trenchclosing sensor showing the drag wire coupled to an instrument disposedin the body of the seed firmer and having a plurality of firmer-mountedsensors.

FIG. 13 illustrates an alternative reference sensor.

FIG. 14 illustrates an alternative reference sensor.

FIG. 15 schematically illustrates one embodiment of a work layer sensor,in elevation view, disposed in relation a seed trench.

FIGS. 16A-16C are representative examples of work layer images generatedby the work layer sensor of FIG. 15 .

FIG. 17 schematically illustrates another embodiment of a work layersensor, in plan view, disposed in relation to a seed trench.

FIG. 18A-18B are representative examples of work layer images generatedby the work layer sensor of FIG. 17 .

FIG. 19 schematically illustrates another embodiment of a work layersensor, in elevation view, disposed in relation to a seed trench.

FIG. 20 is a representative example of a work layer image generated bythe work sensor of FIG. 19 .

FIG. 21 illustrates an embodiment of a work layer implement monitoring,control and operator feedback system.

FIG. 22 is a chart showing a process for work layer implementmonitoring, control and operator feedback.

FIG. 23 is a side elevation view of an embodiment of seed firmer adaptedto function as trench closing sensor showing the fluid tube coupled toan instrument disposed in the body of the seed firmer.

FIG. 24 is a rear view of the closing wheels looking in the direction oftravel positioned over a trench having a seed.

FIG. 25 shows an embodiment of a drag wire with a plurality of wearprotectors disposed over the drag wire.

FIG. 26 is a side elevation view of an embodiment of a seed firmeradapted to function as trench closing sensor showing a detachableportion of the seed firmer with the drag wire in the detachable portion.

FIG. 27A is a side elevation view of another embodiment of a seed firmeradapted to function as trench closing sensor showing the drag wire inthe detachable portion of the seed firmer body.

FIG. 27B is a cross-sectional view along lines B-B of FIG. 27A showingan embodiment of a plate disposed in a detachable portion of the seedfirmer body.

FIG. 28 is a side elevation view of another embodiment of a seed firmeradapted to function as trench closing sensor showing a Hall Effectsensor between two magnets.

FIG. 29 is a side elevation view of a seed firmer adapted to function astrench closing sensor showing a detachable drag wire.

FIG. 30 is a side elevation view of an embodiment of a row unit of anagricultural planter showing an embodiment of a radar sensor formeasuring distance to the ground and to a drag wire.

FIG. 31 illustrates a graph of amplitude versus frequency using theembodiment of FIG. 30 .

FIG. 32A is a side elevation view of an embodiment of a row unit of anagricultural planter showing an embodiment of a Hall effect sensormeasuring distance to a drag wire.

FIG. 32B is a side elevation view of an embodiment of a row unit of anagricultural planter showing an embodiment of a Hall effect sensormeasuring distance to a drag wire having a magnet disposed thereon.

FIG. 33 is a side elevation view of an embodiment of a row unit of anagricultural planter showing an embodiment of an electromagneticinduction sensor measuring distance to a drag wire.

FIG. 34 is a side elevation view of an embodiment of a row unit of anagricultural planter showing an embodiment of a radio frequency systemmeasuring distance between two antennas.

FIG. 35 is a side elevation view of an embodiment of a row unit of anagricultural planter showing an embodiment of an alternative mountingsystem for any of the embodiments in FIGS. 32A to 34 using a ski.

FIG. 36 is a side elevation view of an embodiment of a row unit of anagricultural planter showing an embodiment of a radio frequency systemmeasuring distance between two antennas.

FIG. 37 is a side elevation view of an embodiment of a row unit of anagricultural planter showing an embodiment of a radar sending andreceiving sensor for measuring the depth of a trench.

FIG. 38 illustrates a graph of amplitude versus frequency using theembodiment of FIG. 37 .

DESCRIPTION

Referring now to the drawings, wherein like reference numerals designateidentical or corresponding parts throughout the several views, FIG. 1illustrates an embodiment of an agricultural planter row unit 200. Therow unit 200 is comprised of a frame 204 pivotally connected to atoolbar 202 by a parallel linkage 206 enabling each row unit 200 to movevertically independently of the toolbar 202. The frame 204 operablysupports one or more hoppers 208, a seed meter 210, a seed deliverymechanism 212, a downforce control system 214, a seed trench openingassembly 220, a trench closing assembly 250, a packer wheel assembly260, and a row cleaner assembly 270. It should be understood that therow unit 200 shown in FIG. 7 may be for a conventional planter or therow unit 200 may be a central fill planter, in which case the hoppers208 may be replaced with one or more mini-hoppers and the frame 204modified accordingly as would be recognized by those of skill in theart.

The downforce control system 214 is disposed to apply lift and/ordownforce on the row unit 200 such as disclosed in U.S. Publication No.US2014/0090585, which is incorporated herein in its entirety byreference.

The seed trench opening assembly 220 includes a pair of opening discs222 rotatably supported by a downwardly extending shank member 205 ofthe frame 204. The opening discs 222 are arranged to diverge outwardlyand rearwardly so as to open a v-shaped trench 10 in the soil 11 as theplanter traverses the field. The seed delivery mechanism 212, such as aseed tube or seed conveyor, is positioned between the opening discs 222to deliver seed from the seed meter 210 into the opened seed trench 10.The depth of the seed trench 10 is controlled by a pair of gauge wheels224 positioned adjacent to the opening discs 222. The gauge wheels 224are rotatably supported by gauge wheel arms 226 which are pivotallysecured at one end to the frame 204 about pivot pin 228. A rocker arm230 is pivotally supported on the frame 204 by a pivot pin 232. Itshould be appreciated that rotation of the rocker arm 230 about thepivot pin 232 sets the depth of the trench 10 by limiting the upwardtravel of the gauge wheel arms 226 (and thus the gauge wheels) relativeto the opening discs 222. The rocker arm 230 may be adjustablypositioned via a linear actuator 234 mounted to the row unit frame 204and pivotally coupled to an upper end of the rocker arm 230. The linearactuator 234 may be controlled remotely or automatically actuated asdisclosed, for example, in International Publication No. WO2014/186810,which is incorporated herein in its entirety by reference.

A downforce sensor 238 is configured to generate a signal related to theamount of force imposed by the gauge wheels 224 on the soil. In someembodiments the pivot pin 232 for the rocker arm 230 may comprise thedownforce sensor 238, such as the instrumented pins disclosed in U.S.Pat. No. 8,561,472, which is incorporated herein in its entirety byreference.

The seed meter 210 may be any commercially available seed meter, such asthe fingertype meter or vacuum seed meter, such as the VSet® meter,available from Precision Planting LLC, 23207 Townline Rd, Tremont, IL61568.

The trench closing assembly 250 includes a closing wheel arm 252 whichpivotally attaches to the row unit frame 204. A pair of offset closingwheels 254 are rotatably attached to the closing wheel arm 252 and areangularly disposed to “close” the seed trench 10 by pushing the walls ofthe open seed trench back together over the deposited seed 12. Anactuator 256 may be pivotally attached at one end to the closing wheelarm 252 and at its other end to the row unit frame 204 to vary the downpressure exerted by the closing wheels 254 depending on soil conditions.The closing wheel assembly 250 may be of the type disclosed inInternational Publication No. WO2014/066650, which is incorporatedherein in its entirety by reference.

The packer wheel assembly 260 comprises an arm 262 pivotally attached tothe row unit fame 204 and extends rearward of the closing wheel assembly250 and in alignment therewith. The arm 262 rotatably supports a packerwheel 264. An actuator 266 is pivotally attached at one end to the arm262 and at its other end to the row unit frame 204 to vary the amount ofdownforce exerted by the packer wheel 264 to pack the soil over the seedtrench 10.

The row cleaner assembly 270 may be the CleanSweep® system availablefrom Precision Planting LLC, 23207 Townline Rd, Tremont, IL 61568. Therow cleaner assembly 270 includes an arm 272 pivotally attached to theforward end of the row unit frame 204 and aligned with the trenchopening assembly 220. A pair of row cleaner wheels 274 are rotatablyattached to the forward end of the arm 272. An actuator 276 is pivotallyattached at one end to the arm 272 and at its other end to the row unitframe 204 to adjust the downforce on the arm to vary the aggressivenessof the action of the row cleaning wheels 274 depending on the amount ofcrop residue and soil conditions.

Referring to FIGS. 8 and 9 , a monitor 300 is visible to an operatorwithin the cab of a tractor pulling the planter. The monitor 300 may bein signal communication with a GPS unit 310, the trench closing assemblyactuator 256 and the packer wheel assembly actuator 266 to enableoperational control of the trench closing assembly 250 and the packerwheel assembly 260 (discussed later) based on the signals generated bythe trench closing sensors 1000. Also as discussed later, the monitor300 may be programmed to display operational recommendations based onthe signals generated by the trench closing sensors 1000. The monitor300 may also be in signal communication with the row cleaner actuator276, the downforce control system 214, the depth adjustment actuator 234to enable operational control of row cleaner assembly 270, the downforcecontrol system 214 and the trench opening assembly 230, respectively.

Seed Trench Closing Sensors

FIG. 2 illustrates a trench closing sensor 1000 to determine if theclosing wheel assembly 250 is sufficiently closing the open seed trench10 with soil and/or to determine the amount of compaction of the soilover the seed within the seed trench 10. The trench closing sensor 1000comprises wire, string or other suitable elongate member (hereinafterreferred to as the “drag wire” 1002) disposed to drag in the seed trench10. Generally, as the open seed trench 10 and drag wire 1002 are coveredwith soil by the closing wheel assembly 250 during planting operations,the trench closing sensor 1000 measures or detects whether the seedtrench is being adequately closed with soil by measuring the amount offorce required to pull the wire through the soil or by measuring theamount of strain, pulling force or tension in the wire or by measuringthe amount of soil pressure acting on the wire.

To adequately measure or detect if the seed trench is being adequatelyclosed with soil, the end of the drag wire may terminate proximate tothe vertical axis 1001 extending through the center of the closing wheel254 of the closing wheel assembly 250 of the row unit 200 or severalinches rearward of the vertical axis 1001.

The drag wire 1002 may be supported by any suitable structure thatpermits the rearward end of the drag wire 1002 to drag within the seedtrench 10. For example, the drag wire 1002 may be supported from theseed tube 212, the seed tube guard 290, the shank 205, or from anotherappurtenance 292 aligned with the seed trench. As illustrated in FIG. 10, one such appurtenance 292 may be a seed firmer, such as a Keeton® seedfirmer, or a FurrowJet™, both of which are well known in the art andavailable from Precision Planting, LLC, 23207 Townline Rd, Tremont, IL61568.

FIG. 3 is an embodiment of seed firmer appurtenance 292 adapted tofunction as trench closing sensor 1000. In this embodiment, the plasticbody 1004 of the seed firmer 292 includes a cavity 1006 formed withinthe body. The rearward end of the drag wire 1002 extends outwardly fromthe rear of the body 1004 through an aperture 1008. The forwarded end ofthe drag wire 1002 may be coupled to an instrument 1010 (such straingauge, a hall effect sensor or a potentiometer) disposed within thecavity 1006. The signals generated by the instrument 1010, arecommunicated to the monitor 300 by signal wires 1014.

In an alternative embodiment, any drag wire described herein, such asdrag wire 1002, can be replaced with fluid tube 3002, and instrument1010 is a pressure sensor. FIG. 23 is a modification of FIG. 3 whichshows a trench closing sensor 3000 with a fluid tube 3002. All otheraspects of closing sensor 3000 may remain the same as the closing sensor1000. In this embodiment, the fluid tube 3002 is filled with a fluid(gas or liquid) and connected to instrument 1010. As soil is addedaround fluid tube 3002, fluid tube 3002 compresses, and the pressure influid tube 3002 is increased and is measured by instrument 1010. In oneembodiment, fluid tube 3002 is not elongatable fore to aft (in line withthe direction of travel) so that any pressure change that would becaused by elongation is minimized or eliminated. In such an embodiment,fluid tube may have a rigid side that does not elongate. In oneembodiment, at least 20% or at least 25% of the circumference/perimeterof fluid tube 3002 is rigid and the remainder is compressible. Incross-section, the fluid tube 3002 may be circular or the fluid tube3002 may be square or polygonal in shape and may have one, two, or threerigid sides.

In use, as the row unit 200 travels forwardly, the closing wheels 254 ofthe trench closing assembly 250 close the open seed trench 10 by pushingthe walls of the seed trench 10 back together over the deposited seed 12and the drag wire 1002. As the drag wire 1002 is pulled through the soilof the closed seed trench, the instrument 1010 measures the strain onthe drag wire 1002, or the amount of pulling force or tension exerted onthe drag wire 1002. It should be appreciated that if the seed trench 10is optimally closed producing good seed-to-soil contact, the instrument1010 will measure a greater strain, tension or pulling force than if theseed trench is poorly closed. Likewise, the instrument 1010 can detectif the trench closing assembly 250 is excessively compacting the soil orinadequately packing the soil depending on the strain, tension orpulling force required to pull the drag wire 1002 through the closedtrench.

Rather than measuring the pulling force or tension in the wire, FIG. 4illustrates an embodiment in which a pressure transducer 1012, such as apiezoresistive or piezoelectric transducer, is coupled to the rearwardend of the drag wire 1002 to measure the pressure being exerted on thetransducer 1012 by the surrounding soil pushed into the seed trench 10by the closing wheel assembly 250. The pressure detected by thetransducer 1012 is communicated by signal wires 1014 to the monitor 300.It should be appreciated that the more soil pushed into the seed trench10 by the closing wheel assembly 250, the more soil covers thetransducer 1012 generating a higher pressure measurement. Conversely, ifthe closing wheel assembly is not pushing a sufficient amount of soilinto the seed trench to adequately cover the seed, the transducer 1012will measure a lower pressure.

FIG. 5 illustrates another embodiment in which multiple drag wires1002A, 1002B, 1002C are stacked vertically, each coupled to a respectiveinstrument 1010A, 1010B, 1010C (such strain gauge, a hall effect sensoror a potentiometer) disposed within the cavity 1006 so as to provide aprofile perspective of the trench closure. It should be appreciated thatrather than three drag wires as illustrated in FIG. 4 , there may beonly two stacked drag wires or more than three stacked drag wires.Additionally, it should be appreciated that each of the stacked the dragwires 1002 may be instrumented with a pressure transducer as describedabove or one of more of the stacked wires may be instrumented with apressure transducer while other wires are coupled to an instrument 1010disposed within the cavity 1006. Each drag wire 1002 may have adifferent geometry, length or diameter as compared to other drag wires1002. The different geometries or diameters may provide a differentsignal response for different areas within the trench. Alternatively,instead of vertical alignment, multiple drag wires 1002A, 1002B, 1002Ccan be stacked horizontally (not shown), or a combination of horizontaland vertical stacks (not shown).

In another embodiment, instrument 1010A, 1010B, and 1010C may send anelectrical current to multiple drag wires 1002A, 1002B, and 1002C,respectively. If any of drag wires 1002A, 1002B, or 1002C make contact,an electrical circuit will be formed, and instruments 1010A, 1010B, and1010C may then determine which drag wires 1002A, 1002B, and 1002C are incontact with one another. This information may be sent to monitor 300 bysignal wire 1014. Knowing whether the multiple drag wires 1002A, 1002B,and 1002C are touching provides information about whether multiple dragwires 1002A, 1002B, and 1002C are sensing the same location or differentlocations. When contacted, multiple drag wires 1002A, 1002B, and 1002Care measuring the same location and provides another measurement todetermine whether the furrow is open or closed. For example, if thefurrow is open, multiple drag wires 1002A, 1002B, and 1002C would fallunder gravity and contact one another.

In another embodiment illustrated in FIG. 5A, when multiple drag wires1002A, 1002B, and 1002C or fluid tube 3002 is a non-conductive material,conductive tips 1003A, 1003B, and 1003C may be added to the ends ofmultiple drag wires 1002A, 1002B, and 1002C, respectively, at the endopposite instrument 1010A, 1010B, and 1010C, respectively, or to fluidtube 3002. In such an embodiment, the conductive tips 1003A, 1003B, and1003C are connected to instrument 1010A, 1010B, and 1010C, respectively,by wires 1005A, 1005B, and 1005C, respectively.

In another embodiment as illustrated in FIG. 25 , drag wire 1002 mayfurther include at least one wear protector 1009 disposed over drag wire1002. Wear protector 1009 may be a single piece, or wear protector 1009can be a plurality of pieces. Whether as a single piece or as aplurality of pieces, wear protector 1009 may cover from greater than 0up to 100% of drag wire 1002. In certain embodiments, the percentage ofcoverage of drag wire 1002 extending from body of the firmer is 40 to60%, about 50%, greater than 90%, or 95-99%. Wear protector 1009 may bemade from any material that increases wear resistance compared to thematerial of drag wire 1002. In one embodiment, wear protector 1009 ismade from tungsten carbide. Tungsten carbide can provide increase wearresistance, but tungsten carbide can be brittle. As such, in oneembodiment, a wear protector 1009 made from tungsten carbide is aplurality of pieces, such as shown in FIG. 25 .

FIG. 26 illustrates another embodiment of a trench closing sensor 4000.In this embodiment, trench closing sensor 4000 has a first body 4004 anda second body 4001. The second body 4001 may be detachable from thefirst body 4004 by any suitable attachment, such as a fastener, nut andbolt, screw, and/or clip. The second body 4001 has a member 4003 (suchas a plate) attached to a pivot 4002 at one end, and drag wire 1002 isdisposed at the other end of 4003. The drag wire 1002 is then disposedthrough second body 4001 and extends rearward. Plate 4003 pivots aboutpivot 4002 and extends downward. A biasing element 4005 (such as aspring) biases plate 4003 forward towards the first body 4004. A stop(not shown) may be provided to prevent movement of plate 4003 too farforward. In a neutral position in one embodiment, plate 4003 isperpendicular to the ground. Disposed on plate 4003 is a transmitter4007 (such as a magnet). Transmitter 4007 generates a signal (such as amagnetic field) that is detected by a receiver 4008 (such as a HallEffect sensor) disposed in the first body 4004. In one embodiment, thetransmitter 4007 may be disposed on plate 4003 on the side facing thefirst body 4004. Receiver 4008 is then in communication with monitor 300through signal wire 1014. Receiver 4008 may first be disposed on acircuit board (not shown) and then connected to signal wire 1014, suchas illustrated in FIG. 12 in which other sensors (such as reflectivityor temperature sensors) are disposed in the first body 4004 andconnected to a circuit board.

As drag wire 1002 is pulled by contact with soil, plate 4003 will pivotrearward, and the distance between transmitter 4007 and receiver 4008will increase and change the signal (magnetic field) measured byreceiver 4008. When drag wire 1002 becomes worn, trench closing sensor4000 provides for easier replacement of the drag wire 1002 by removingsecond body 4001 and replacing it with a new second body 4001. Thissaves time by not having to open the body 4004 in trench closing sensor4000.

In an alternative to the previous embodiment and illustrated in FIGS.27A and 27B, resilient plate 4009 replaces plate 4003 and pivot 4002.Transmitter 4007 is disposed on plate 4009 as with plate 4003. In thisembodiment, resilient plate 4009 deflects when drag wire 1002 pulls onplate 4009, and 4009 returns to its original position when no force isapplied. As illustrated in FIG. 27B, plate 4009 may have a T shape.

In another embodiment illustrated in FIG. 28 , transmitter 4007 andreceiver 4008 are replaced by sensor system 4030. For illustrationpurposes, sensor system 4030 is shown with the embodiment of FIG. 27A.Sensor system 4030 includes a first magnet 4031, a second magnet 4032,and a Hall Effect sensor 4033. First magnet 4031 and second magnet 4032are disposed in a body/bodies (such as 1004, 4001, 4004) so that thesame poles (both N-N or S-S) are oriented towards each other. HallEffect sensor 4033 is disposed equidistant from first magnet 4031 andsecond magnet 4032 so that the field measured at this middle point iszero. The benefit of having this configuration is that the full voltagerange for the Hall Effect sensor 4033 is available to measure the fieldin the compressed space as compared to only having half of the voltagerange available to read the field at a distance from to infinity. Firstmagnet 4031 is disposed on plate 4009 or plate 4003.

While illustrated with two bodies 4001 and 4004, any of the embodimentsin FIG. 26, 27A, or 28 may be used in a single body (not shown).

In another embodiment illustrated in FIG. 29 , any of the drag wires1002 described herein can be made in two parts, a drag wire base section1002B and drag wire end 1002A, and connected at detachable connection1011. Having the detachable drag wire end 1002A allows for replacementof the drag wire without having to open body 1004 (or body 4001).

Referring again to FIG. 8 , the signals generated by the trench closingsensor 1000, 3000, 4000 may be communicated by signal wires 1014 to themonitor 300 as the actual measurement or the monitor 300 may beprogrammed to convert and display on the monitor screen the actualforce, tension or pressure measured by the sensor 1000, 3000, 4000 inthe seed trench 10 in relation to a desired force, tension or pressurerange. If the desired displayed force, tension or pressure is outsidethe desired range, the downforce on the closing wheel 254 may beadjusted. The adjustment of the closing wheel downforce may be adjustedmanually by adjusting the position of a conventional coil springcorresponding to discrete preload settings. Alternatively, if theclosing wheel assembly 250 is equipped with trench closing wheelassembly actuator 256 as previously described, the operator may manuallyactuate the trench closing wheel assembly actuator 256 as needed toincrease or decrease the amount of downforce exerted by the closingwheels 254 to keep the force, tension or pressure measured by the trenchclosing sensor 1000 within the desired range. Alternatively, the monitor300 may be programmed to automatically actuate the trench closing wheelassembly actuator 256 to increase or decrease the downforce on theclosing wheels 254 depending on whether the trench closing sensor 1000detects that the force, tension or pressure on the drag wire(s) 1002falls below or exceeds a predefined minimum and maximum threshold force,tension or pressure. In yet another embodiment, rather than adjustingthe downforce on the closing wheel assembly 250 via a conventional coilspring or actuator, the angle of the closing wheels may be adjusted toincrease or decrease the aggressiveness of the closing wheels. Forexample, as is known in the art, an actuator or mechanical adjustment(not shown) may be provided to decrease or increase the angle of theclosing wheels with respect to the direction of travel or with respectto vertical thereby adjusting the amount of soil the closing wheels pushinto the seed trench. If a closing wheel angle actuator is provided toadjust the closing wheel angle, the operator may actuate the actuatormanually or the monitor 300 may be programmed to automatically actuatethe actuator to adjust the aggressiveness of the closing wheelsdepending on the force, tension or pressure detected by the trenchclosing sensor 1000, 3000, 4000.

In another embodiment illustrated in FIG. 24 , the camber angle of theclosing wheels can be adjusted so that axis A-1 and A-2 through theclosing wheels 254-1 and 254-2 intersect the seed 12 in the trench 10.The work layer sensors described below can be used to locate the seed 12in the trench 10. The position of the closing system 250 with respect toany of the work layer sensors is known, and closing wheels 254-1 and254-2 may be adjusted by actuator 259 to adjust the camber angle ofclosing wheels 254-1 and 254-2. Alternatively, the camber angle may beadjusted to intersect the bottom of trench 10. In certain embodiments,it may be assumed that seed 12 is at the bottom of trench 10. The bottomof trench 10 may be determined by any instrument that determines thedepth of trench 10. Non-limiting examples of instruments that maydetermine the depth of trench 10 are disclosed in CN101080968,CN201072894, DE102004011302, JP0614628, JP2069104, JP04360604,JP08168301, JP2001299010, JP2006345805, U.S. Pat. Nos. 4,413,685,4,775,940, 5,060,205, 6,216,795, 8,909,436, US20150289438,US20160037709, WO2012102667, WO2015169323, and U.S. ProvisionalApplication No. 62/365,585, all of which are incorporated herein byreference with respect to the disclosed distance/depth determinationsubject matter. The angle may then be determined by assuming that thetrench is centered between closing wheels 254-1 and 254-2. In theembodiment of FIG. 24 , closing system 250 includes a closing framemember 253. Closing wheels 254-1 and 254-2 are attached to axles 255-1and 255-2, respectively. Axles 255-1 and 255-2 are connected to axlearms 257-1 and 257-2, respectively, which are pivotably connected toframe member 253 and actuator arms 258-1 and 258-2, respectively, whichare pivotably connected to the actuator 259. The actuator 259 is incommunication with monitor 300, wherein the actuator 259 receivessignals to rotate, which causes actuator arms 258-1 and 258-2 to movecloser or farther from the center of closing frame 253 to cause theangle of axle arms 257-1 and 257-2 with respect to closing frame member253 to change, which, in turn, changes the camber angles of closingwheels 254-1 and 254-2. While shown with one actuator 259, there can betwo actuators 259-1 and 259-2 with axle arm 258-1 connected to actuator259-1 and axle arm 258-2 connected to actuator 259-2 to allow forindependent adjustment of the camber angles of closing wheels 254-1 and254-2 (not shown).

Packer Wheel Adjustment

Alternatively, or additionally, the packer wheel assembly 260 may beadjusted based on the tension, pulling force or pressure detected by thedrag wire(s) 1002. The adjustment of the packer wheel downforce may beadjusted manually by adjusting the position of a conventional coilspring corresponding to discrete preload settings, or, if the packerwheel assembly 260 is equipped with an actuator 266 as previouslydescribed, the operator may manually actuate the actuator 266 or themonitor 300 may be programmed to automatically actuate the actuator 266to increase or decrease the amount of downforce exerted on the packerwheel 264 to keep the force, tension or pressure measured by the trenchclosing sensor 1000, 3000, 4000 within the desired range.

Reference Sensor and Trench Closing Sensor Calibration

A reference sensor 1100 (FIGS. 2, 6 and 7 ) may be provided to“calibrate” the trench closing sensor 1000, 3000, 4000 to account forconditions that may have an effect on the drag coefficient properties ofthe soil, including such factors as planter speed, trench depth, soiltexture, soil moisture and soil density. As best illustrated in FIGS. 6and 7 , the reference sensor 1100 includes a drag member 1102 which isdisposed to drag through the soil outside of the seed trench 10. Thereference sensor 1100 may be disposed forward of the trench openingassembly 220 as shown in FIG. 2 or the drag member 1102 may be mountedbetween the row units 200 (not shown). The drag member 1102 is supportedby an arm 1104 which is adjustably positionable with respect to a gaugewheel 1106 to vary the penetration depth of the drag member 1102 withrespect to the soil surface. The arm 1104 is instrumented with a straingauge 1110 to detect the strain exerted on the arm 1104 as the dragmember 1102 drags through the soil. Signal wires 1114 transmit theelectrical resistance change in the strain gauge 1110 to the monitor300. The monitor 300 is programmed to correlate the electricalresistance change to detected strain in the arm 1104 which can then becorrelated with the signals generated by the trench closing sensor 1000to define the range of the force, tension or pressure that the trenchclosing sensor 1000 should be detecting if the seed trench is beingadequately closed by the trench closing assembly 250.

In other embodiments, the reference sensor 1100 may be the penetrationforce of row unit 200. The penetration force be measured directly withforce sensor 223, such as a strain gauge, disposed at the opener discspindle 225 as illustrated in FIG. 2 . The penetration force of row unit200 may also be determined by subtracting the gauge wheel force measuredby downforce sensor 238 from the applied force as applied by thedownforce control system 214 and the mass of row unit 200.

In other embodiments, the reference sensor 1100 may be the electricalconductivity or reflectance of the soil. Suitable sensors for electricalconductivity and reflectance are described in WO2015/171908, which isincorporated herein by reference in its entirety. In one embodimentillustrated in FIG. 12 , the seed firmer appurtenance 292 of FIG. 3further contains the reflectivity sensors 350 a and 350 b, electricalconductivity sensors 370 f and 370 r of seed firmer 400 shown in FIG. 4aof WO2015/171908. While this embodiment shown a wireless transmitter62-1, which is in data communication with monitor 300, the datacommunication to monitor 300 can be wired. Also shown in FIG. 12 (fromFIG. 4A from WO2015/171908) is temperature sensor 360, removable portion492, male coupler 472, and female coupler 474.

In another embodiment, the reference sensor 1100 may be the geospatialsoil type information based on GPS location, such as the USDA SSURGOdata, which may be useful when changing zones in the field. The data foreach zone in the field can be the reference.

An alternative reference sensor 1100A, illustrated in FIG. 13 , includesa coulter arm 2001 attached to row unit 200 with a coulter 2002 attachedto coulter arm 2001 with axle 2003. At axle 2003, a force sensor 2004,such as downforce sensor 238, measures the force that coulter 2002transmits to axle 2003. Force sensor 2004 is in data communication withmonitor 300.

An alternative reference sensor 1100B, illustrated in FIG. 14 , includesarm 3001 mounted to row unit 200 (or alternatively to toolbar 202), andat the opposite end of arm 3001 is bracket 3002. To bracket 3002, acoulter arm 3003 is pivotably mounted, and a force device 3004, such asa spring, is disposed to connect coulter arm 3003 to bracket 3002 toapply a fixed force to coulter arm 3003. Alternatively, the force devicemay be a pneumatic device, hydraulic device, an electromechanicaldevice, or an electro-hydraulic device. A coulter 3008 is rollinglymounted to coulter arm 3003. A gauge wheel arm 3005 is pivotablyconnected to coulter arm 3003, and a gauge wheel 3007 is rollinglymounted to gauge wheel arm 3005. An angle sensor 3006 is disposed at thepivoting connection between gauge wheel arm 3005 and coulter arm 3003.Examples of angle sensor 3006 include, but are not limited to, a rotarypotentiometer or Hall-effect sensor. Angle sensor 3006 is in datacommunication with monitor 300. In this embodiment, force device 3004applies a known force to coulter 3008. As the hardness of the soilchanges, gauge wheel arm 3005 will rotate, and angle sensor 3006measures the amount of rotation.

Another reference sensor that may be used in conjunction with trenchclosing sensor 1000, 3000, 4000 is the speed of row unit 200. As thespeed of travel changes, the force, tension or pressure measured willdirectly change with the change in speed. The speed of row unit 200 maybe determined by any suitable device, such as a speedometer on thetractor (tractor wheel speed), GPS distance change over time, or groundspeed radar. Any of these devices may be in data communication withmonitor 300.

Operator Feedback to Control Closing Wheel Assembly

FIG. 9 is a schematic illustration of a system 500 which employs thetrench closing sensors 1000, 3000, 4000 and reference sensors 1100 toprovide operator feedback and to control the closing wheel assembly 250and packer wheel assembly 260 of the planter row unit 200. At steps 510and 512, the reference sensor 1100 detects the strain (via the straingauge 1110) exerted on the arm 1104. At step 512, the strain exerted onthe arm 1104 is correlated to define the range of force, tension orpressure that should be detecting if the seed trench is being adequatelyclosed by the trench closing assembly 250. At step 514 the trenchclosing sensor 1000, 3000, 4000 detects the force, tension or pressureexerted by the soil on the drag wire(s) 1002. At step 516 the force,tension or pressure exerted by the soil on the drag wire(s) 1002 of thetrench closing sensor 1000, 3000, 4000 may be displayed to the operatoron the monitor 300 in the cab of the tractor in relation to thecorrelated range of the force, tension or pressure that the trenchclosing sensor 1000, 3000, 4000 should be detecting if the seed trenchis being adequately closed by the trench closing assembly 250. At step518, control decisions are made based on the comparison of thecharacterized range with the force, tension or pressure detected by thatthe trench closing sensor 1000, 3000, 4000. At step 520, the closingwheel assembly 250 or the packer wheel assembly 260 may be controlled bythe monitor 300 generating signals to actuate one or more of thecorresponding actuators 256, 266 and/or at step 522, correspondingrecommendations may be displayed to the operator on the monitor display.

Other Trench Sensor Systems

FIG. 10 shows an embodiment of a trench sensor system 2000. The trenchsensor system 2000 has one or both of a trench sensor 2010 and groundsensor 2020. Trench sensor 2010 is disposed on closing system 250 afterthe opening assembly 220 in a direction of travel to sense the distanceto the bottom of seed trench 10. Ground sensor 2020 is disposed on rowunit 200 after trench sensor 2010 in a direction of travel to sense thedistance to soil surface 1. Both trench sensor 2010 and ground sensor2020 are at a fixed distance to the bottom of closing wheels 254, andboth are in communication with monitor 300. The depth (HG) of closingwheels 254 in the soil can be determined by subtracting a distancemeasured by ground sensor 2020 from the distance of ground sensor 2020to the bottom of closing wheels 254. The distance (HF) of closing wheels254 above the bottom of seed trench 10 can be determined by subtractingthe distance of trench sensor 2010 to the bottom of closing wheels 254from a distance measured by trench sensor 2010. One or both of thesemeasurements may also be used in combination with the measurements ofthe trench closing sensor 1000, 3000, 4000 to determine closingeffectiveness. Trench sensor 2010 and ground sensor 2020 may eachindependently be an ultrasonic sensor, radar, or a laser.

In another embodiment as illustrated in FIG. 11 , an angle sensor 2280can be disposed at the connection of closing wheel arm 252 and frame204, and angle sensor 2280 is in communication with monitor 300. Theangle sensor 2280 can be the same as the pivot arm angle sensor 280 inWO2014/066650. The angular output of angle sensor 2280 can be combinedwith the measurements of the trench closing sensor 1000, 3000, 4000 todetermine closing effectiveness of the seed trench. Examples of anglesensor 2280 include, but are not limited to, rotary potentiometer andHall-effect sensor.

Work Layer Imaging

Referring to FIG. 2 , Work layer sensors 100, such as disclosed in PCTApplication No. PCT/US2016/031201, which is incorporated herein in itsentirety by reference, may be disposed on row unit 200 to generate asignal or image representative of the soil densities or other soilcharacteristics throughout a soil region of interest, hereinafterreferred to as the “work layer” 104. Work layer sensors 100 maydetermine the effectiveness of the closing of the trench to identify ifthere are any void spaces in the closed trench. The work layer sensorsmay be used in conjunction with the trench closing sensor 1000, 3000,4000.

FIGS. 15, 17 and 19 schematically illustrate alternative embodiments ofa work layer sensor 100. The representative image or signal generated bythe work layer sensor 100 is hereinafter referred to as the “work layerimage” 110. In one particular application discussed later, the worklayer sensors 100 may be mounted to a planter row unit 200 (FIG. 1 ) forgenerating a work layer image 110 of the seed trench as the plantertraverses the field. The work layer image 110 may be displayed on amonitor 300 visible to an operator within the cab of a tractor and theplanter may be equipped with various actuators for controlling theplanter based on the characteristics of the work layer 104 as determinedfrom the work layer image 110.

The work layer sensor 100 for generating the work layer image 110 maycomprise a ground penetrating radar system, an ultrasound system, anaudible range sound system, an electrical current system or any othersuitable system for generating an electromagnetic field 102 through thework layer 104 to produce the work layer image 110. It should beunderstood that the depth and width of the work layer 104 may varydepending on the agricultural implement and operation being performed.

FIG. 15 is a schematic illustration of one embodiment of a work layersensor 100-1 disposed in relation to a seed trench 10 formed in the soil11 by a planter, wherein the seed trench 10 comprises the soil region ofinterest or work layer 104. In this embodiment, the work layer sensor100-1 comprises a transmitter (T1) disposed on one side of the seedtrench 10 and a receiver (R1) disposed on the other side of the seedtrench 10 to produce the electromagnetic field 102 through the seedtrench to generate the work layer image 110.

In some embodiments, the work layer sensor 100 may comprise aground-penetration radar subsurface inspection system such as any of thefollowing commercially available systems: (1) the StructureScan™ Mini HRavailable from GSSI in Nashua, New Hampshire; (2) the 3d-Radar GeoScope™Mk IV coupled to a 3d-Radar VX-Series and/or DX-Series multi-channelantenna, all available from 3d-Radar AS in Trondheim, Norway; or (3) theMALA Imaging Radar Array System available from MALA Geoscience in Mala,Sweden. In such embodiments, the commercially available system may bemounted to the planter or other implement, or may be mounted to a cartwhich moves with the implement; in either case the system is preferablydisposed to capture an image of a work layer in the area of interest(e.g., the seed trench). In some embodiments, the work layer image 110may be generated from the signal outputs of the work layer sensor 100using commercially available software such as GPR-SLICE (e.g., version7.0) available from GeoHiRes International Ltd. located in Borken,Germany.

FIGS. 16A-16C are intended to be representative examples of work layerimages 110 generated by the work layer sensor 100-1 of FIG. 15 showingvarious characteristics of the seed trench 10, including, for example,the trench depth, the trench shape, depth of seed 12, the seed depthrelative to the trench depth, crop residue 14 in the trench, and thevoid spaces 16 within the trench. As described in more detail later, thework layer images 110 may be used to determine other characteristics ofthe work layer 104, including, for example, the seed-to-soil contact,percentage of trench closed, percentage of upper half of trench closed,percentage of lower half of trench closed, moisture of the soil, etc.

FIG. 17 schematically illustrates, in plan view, another embodiment of awork layer sensor 100-2 disposed with respect to a seed trench 10. Inthis embodiment, a transmitter (T1) is disposed on one side of the seedtrench 10, a first receiver (R1) is disposed on the other side of theseed trench 10, and a second receiver (R2) is disposed adjacent andrearward of the transmitter (T1). FIG. 18A is a representativeillustration of the work layer image 110 generated through the trenchbetween the transmitter (T1) and the first receiver (R1)) and FIG. 18Bis a representative illustration of the work layer image 110 generatedbetween the transmitter (T1) and the second receiver (R2) providing animage of the undisturbed soil adjacent to the seed trench.

FIG. 19 is an elevation view schematically illustrating another worklayer sensor embodiment 100-3 disposed with respect to a seed trench 10.In this embodiment, the work layer sensor 100-3 comprises a plurality oftransmitter and receiver pairs disposed above and transverse to the seedtrench 10.

FIG. 20 is a representative illustration of the work layer image 110generated by the work layer sensor 100-3 of FIG. 5 which provides a viewnot only of the seed trench but also a portion of the soil adjacent toeach side of the seed trench.

For each of the work layer sensor embodiments 100-1, 100-2, 100-3, thefrequency of operation of the work layer sensors 100 and the verticalposition of the transmitters (T) and receivers (R) above the soil andthe spacing between the transmitters (T) and receivers (R) are selectedto minimize signal to noise ratio while also capturing the desired depthand width of the soil region of interest (the work layer 104) for whichthe work layer image 110 is generated.

Work Layer Imaging for Planter Applications

FIG. 1 illustrates one example of a particular application of the worklayer sensors 100 disposed on a row unit 200 of an agricultural planter.The row unit 200 includes a work layer sensor 100A disposed on a forwardend of the row unit 200 and a work layer sensor 100B disposed rearwardend of the row unit 200. The forward and rearward work layer sensors100A, 100B may comprise any of the embodiments of the work layer sensors100-1, 100-2, 100-3 previously described.

The forward work layer sensor 100A is disposed to generate a referencework layer image (hereinafter a “reference layer image”) 110A of thesoil prior to the soil being disturbed by the planter, whereas therearward work layer sensor 100B generates the work layer image 110B,which in this example, is the image of the closed seed trench 10 inwhich the seed has been deposited and covered with soil. For the reasonsexplained later, it is desirable to obtain both a reference image 110Aand the work layer image 110B for analysis of the soil characteristicsthrough the work layer 104.

It should be appreciated that the forward and rearward work layersensors 100A, 100B referenced in FIG. 1 may employ any of theembodiments 100-1, 100-2 or 100-3 previously described. However, itshould be appreciated that if the embodiments 100-2 or 100-3 areemployed, the forward work layer sensor 100A may be eliminated becausethe embodiments 100-2 and 100-3 are configured to generate the worklayer images 110 of undisturbed soil adjacent to the seed trench 10which could serve as the reference layer image 110A.

It should be appreciated that rather than positioning the work layersensors 100 as shown in FIG. 1 , the work layer sensors may bepositioned after the row cleaner assembly 270 and before the trenchopening assembly 220 or in one or more other locations between thetrench opening discs 222 and the closing wheels 254 or the packing wheel264 depending on the soil region or characteristics of interest.

Planter Control and Operator Feedback Using Work Layer Imaging

FIG. 21 is a schematic illustration of a system 600 which employs worklayer sensors 100 to provide operator feedback and to control theplanter row unit 200. Work layer sensors 100A, 100B are disposed togenerate a reference layer image 110A of undisturbed soil and a worklayer image 110B of the closed seed trench (i.e., after seed isdeposited, covered with soil by the closing wheel assembly 250 and thesoil packed with the packing wheel assembly 260). As previouslydescribed, the work layer sensors 100A, 100B may be separate work layersensors disposed forward and rearward of the row unit 200 as illustratedin FIG. 7 , or the work layer sensors 100A, 100B may comprise a singlework layer sensor with transmitters (T) and receivers (R) disposed togenerate both a reference layer image 110A and a work layer image 110B.

The work layer image 110B may be communicated and displayed to theoperator on a monitor 300 comprising a display, a controller and userinterface such as a graphical user interface (GUI), within the cab ofthe tractor.

The monitor 300 may be in signal communication with a GPS unit 310, therow cleaner actuator 276, the downforce control system 214, the depthadjustment actuator 234, the trench closing assembly actuator 256 andthe packer wheel assembly actuator 266 to enable operational control ofthe planter based on the characteristics of the work layer image 110B.

For example, if the work layer image 110B indicates that residue in theseed trench 10 is above a predetermined threshold (as explained below),a signal is generated by the monitor 300 to actuate the row cleaneractuator 276 to increase row cleaner downforce. As another example, ifthe seed depth is less than a predetermined threshold (as explainedbelow), a signal is generated by the monitor 300 to actuate thedownforce control system 214 to increase the downforce and/or to actuatethe depth adjustment actuator 234 to adjust the gauge wheels 234relative to the opening discs 232 to increase the trench depth. Likewiseif the seed depth is greater than a predetermined threshold, a signal isgenerated by the monitor 300 to actuate the downforce control system 214to decrease the downforce and/or to actuate the depth adjustmentactuator 234 to decrease the trench depth. As another example, if theupper portion of the trench has more than a threshold level of voidspace (as explained below), a signal is generated by the monitor 300 toactuate the trench closing wheel assembly actuator 256 to increase thedownforce on the closing wheels 254. As another example, if the lowerportion of the trench has more than a threshold level of void space (asexplained below), a signal is generated by the monitor 300 to actuatethe packer wheel assembly actuator 266 to increase the downforce on thepacker wheel 264.

In still other examples, the work layer image 110B may identify and/oranalyze (e.g., determine depth, area, volume, density or other qualitiesor quantities of) subterranean features of interest such as tile lines,large rocks, or compaction layers resulting from tillage and other fieldtraffic. Such subterranean features may be displayed to the user on themonitor 300 and/or identified by the monitor 300 using an empiricalcorrelation between image properties and a set of subterranean featuresexpected to be encountered in the field. In one such example, the areatraversed by the gauge wheels (or other wheels) of the planter (ortractor or other implement or vehicle) may be analyzed to determine adepth and/or soil density of a compaction layer beneath the wheels. Insome such examples, the area of the work layer image may be divided intosubregions for analysis based on anticipated subterranean features insuch sub-regions (e.g., the area traversed by the gauge wheels may beanalyzed for compaction).

In other examples, the monitor 300 may estimate a soil property (e.g.,soil moisture, organic matter, or electrical conductivity, water tablelevel) based on image properties of the work layer image 110B anddisplay the soil property to the user as a numerical (e.g., average orcurrent) value or a spatial map of the soil property at geo-referencedlocations in the field associated with each soil property measurement(e.g., by correlating measurements with concurrent geo-referencedlocations reported the GPS unit 310).

Alternatively or additionally, the monitor 300 could be programmed todisplay operational recommendations based on the characteristics of thework layer image 110B. For example, if the work layer image 110Bidentifies that the seed 12 is irregularly spaced in the trench 10 or ifthe seed 12 is not being uniformly deposited in the base of the trench,or if the spacing of the seed 12 in the trench does not match theanticipated spacing of the seed based on the signals generated by theseed sensor or speed of the seed meter, such irregular spacing,nonuniform positioning or other inconsistencies with anticipated spacingmay be due to excess speed causing seed bounce within the trench orexcess vertical acceleration of the row unit. As such, the monitor 300may be programmed to recommend decreasing the planting speed or tosuggest increasing downforce (if not automatically controlled aspreviously described) to reduce vertical acceleration of the planter rowunits. Likewise to the extent the other actuators 276, 214, 234, 256,266 are not integrated with the monitor controller, the monitor may beprogrammed to display recommendations to the operator to make manual orremote adjustments as previously described based on the characteristicsof the work layer image 110B.

FIG. 22 illustrates the process steps for controlling the planter andproviding operator feedback. At steps 610 and 612, the reference image110A and work layer image 110B is generated by the work image sensor(s)100. At step 614, the work layer image 110B may be displayed to theoperator on the monitor 300 in the cab of the tractor. At step 616, thereference layer image 110A is compared with the work layer image 110B tocharacterize the work layer image. At step 618, the characterized worklayer image 110B is compared to predetermined thresholds. At step 620,control decisions are made based on the comparison of the characterizedwork layer image 110B with the predetermined thresholds. At step 622,the planter components may be controlled by the monitor 300 generatingsignals to actuate one or more of the corresponding actuators 276, 214,234, 256, 266 and/or at step 624, corresponding recommendations may bedisplayed to the operator on the monitor display.

To characterize the work layer image 110B at step 616, the monitor 300compares one or more characteristics (e.g., density) of the referenceimage 110A with the same characteristics of the work layer image 110B.In some embodiments, a characterized image may be generated comprisingonly portions of the work layer image differing from the reference imageby at least a threshold value. The characterized image may then be usedto identify and define features of the work layer image 110B, such asthe trench shape, the trench depth, residue in the trench, seeds andseed placement within the trench, void spaces within the trench, anddensity differences of the soil within the trench.

For example, to determine the seed depth, the seed is identified oridentifiable from the work layer image 110B by determining regionswithin the work layer image having a size or shape corresponding to aseed and having a density range empirically corresponding to seed.

Once a region is identified as a seed, the vertical position of the seedwith respect to the soil surface is readily measurable or determined.

As another example, the amount of residue in the trench can bedetermined by (a) defining the area of the trench cross-section (basedon soil density differences between the reference image 110A and thework layer image 110B); (b) by identifying the regions within the trenchhaving a density range empirically corresponding to residue; (c)totaling the area of the regions corresponding to residue; and (d)dividing the residue area by the trench cross-sectional area.

Seed Trench Depth Detection

FIG. 30 illustrates an embodiment for detecting seed trench depthutilizing a radar 710 disposed on the trench closing assembly 250 tosend a signal to the ground and to an elongate member 800 (such as thedrag wire 1002 described above). Radar 710 is in signal communicationwith monitor 300. In one embodiment, the radar 710 uses a frequencymodulated continuous wave signal. Two reflections are returned to radar710. As illustrated in FIG. 31 , an amplitude versus frequency graphwill show a first peak 711 representing the ground reflection and asecond peak 712 representing drag wire 1002 reflection. Depthmeasurement is proportional to the frequency difference between firstpeak 711 and second peak 712. Also, radar 710 may provide the surfaceprofile of the closed trench, which can be achieved using a TexasInstruments mmWave chip in radar 710. As can be appreciated, a lowerfrequency for radar 710 will provide increased soil penetration but willdecrease resolution. In this embodiment, elongate member 800 only needsto reflect a radar signal, but elongate member 800 can be any elongatemember described above, such as drag wire 1002 or fluid tube 3002. Radar710 can be used in conjunction with any of the following embodiments.

FIG. 32A illustrates an embodiment for detecting seed trench depthutilizing a Hall effect sensor 720 to measure distance to an elongatemember 800. The elongate member 800 may be a looped wire 801 with acurrent flowing through the looped wire 801 to generate a magneticfield. The Hall effect sensor 720 is connected to the agriculturalimplement (agricultural row planter row unit 200 as illustrated) and isbiased to engage the ground above looped wire 801. As illustrated, Halleffect sensor 720 is attached to closing system 250 through biasingelements 729 (e.g., springs). Both Hall effect sensor 720 and loopedwire 801 are in signal communication with monitor 300. To increase theability of Hall effect sensor 720 reading the magnetic signal fromlooped wire 801, the current in looped wire 801 can be cycled on andoff. Other parts on the agricultural implement can produce interferencewhen traveling over or through the ground. By cycling looped wire 801off, the signal read by Hall effect sensor 720 can be taken asbackground noise, which can then be subtracted from the total signalwhen current is flowing through looped wire 801. The strength of themagnetic field read by Hall effect sensor 720 is proportional to thedepth. In another embodiment, instead of a looped wire 801 with currentto generate a magnetic field, elongate member 800 can have a magnet 802disposed on elongate member 800, which is illustrated in FIG. 32B.

FIG. 33 illustrates an embodiment for detecting seed trench depth andutilizing similar structure to FIG. 32B, except that an electromagneticinduction (EMI) coil 730 is used in place of Hall effect sensor 720. EMIcoil 730 is in signal communication with monitor 300. Elongate member800 causes a change in induction, which can be read as distance toelongate member 800 (depth). In another embodiment, there can be aplurality of EMI coils 730, which can be at different frequencies, tobetter account for any noise.

FIG. 34 illustrates an embodiment for detecting seed trench depthutilizing a radio signal generator and phase detector 740 (which couldbe two separate components) disposed on the agricultural implement, suchas on closing system 250, and generates a radio signal. Elongate member800 can either be the transmitting antenna or the receiving antenna, andantenna 741 is either the receiving antenna or transmitting antennaopposite elongate member 800. Radio signal generator and phase detector740 is in signal communication with monitor 300. A radio frequency isgenerated and transmitted by elongate member 800 (or antenna 741) andreceived by antenna 741 (or elongate member 800). The frequency used isgenerally two times the expected depth but short enough for adequateresolution. Depth is a function of the phase shift between thetransmitted and received signals. In another embodiment, antenna 741 canbe disposed on a mud flap (not shown) connected to and disposed afterthe closing system 250.

FIG. 35 illustrates an alternative embodiment for detecting seed trenchdepth for any of the embodiments of FIGS. 32A-34 utilizing biasingelements 729. The biasing elements 729 may be replaced with a bracket725 as shown in FIG. 35 which is connected to the agriculturalimplement, such as closing system 250. A ski 727 is attached through abiased pivot 726 to bracket 725 to bias any of Hall effect sensor 720,EMI coil 730, or antenna 741 to the ground to maintain contact with theground. In FIG. 35 , Hall effect sensor 720 is illustrated, but EMI coil730 or antenna 741 can replace Hall effect sensor 720.

FIG. 36 illustrates an embodiment for detecting seed trench depthutilizing an antenna 742 pivotally connected to body 1004 and biased tocontact the ground adjacent the trench to maintain contact with thetrench. As with the embodiment in FIG. 34 , elongate member 800 mayeither be the transmitting antenna or the receiving antenna. Antenna 742is either the receiving antenna or transmitting antenna oppositeelongate member 800. Radio signal generator and phase detector 740 is insignal communication with the monitor 300. A radio frequency isgenerated and transmitted by elongate member 800 (or antenna 742) andreceived by antenna 742 (or elongate member 800). The frequency used isgenerally two times the expected depth but short enough for adequateresolution. Depth is a function of the phase shift between thetransmitted and received signals.

FIG. 37 illustrates an embodiment for detecting seed trench depthutilizing an antenna 743 connected to body 1004 and is disposedrearwardly and above elongated member 800 but not as far as elongatedmember 800. Both extend into the closed trench. A gap in the lengths ofelongated member 800 and antenna 743 is needed for the radar signal. Aradar 750 may be disposed in body 1004. Radar 750 is in signalcommunication with monitor 300. In one embodiment, the radar 750 uses afrequency modulated continuous wave signal. Elongate member 800 iseither a transmitting or receiving antenna connected to radar 750, andantenna 743 is either the receiving antenna or transmitting antennaopposite elongate member 800. A radar signal is directed up fromelongate member 800 (or antenna 743) and is received by antenna 743 (orelongate member 800). As illustrated in FIG. 38 , a graph of amplitudeversus frequency will show a first peak 751 and a second peak 752. Firstpeak 751 represents the reflection of the ground surface in the closedtrench. Second peak 752 represents noise. Depth measurement isproportional to the frequency of first pulse 753.

It should be appreciated that for each of the above embodiments fortrench depth detection, the elongate member 800 may be the drag wire1002 described above in connection with the trench closing sensors orthe elongate member described in each of the embodiments of FIGS. 30 and32-37 .

Once trench depth is known, the trench depth can be changed by anyactuator that changes trench depth. Examples of actuators to modifytrench depth can be found in International Patent Application Nos.PCT/US2017/18274 and PCT/US2017/18269, both of which are incorporatedherein by reference in their entireties.

In another embodiment, radar 710 can be disposed on the trench closingassembly 250 as is illustrated in FIG. 30 . In this embodiment, radar710 can alternatively be an ultrasonic transceiver. The trench closingsensorS 1000, 3000, 4000 or the trench depth measuring devices above arenot required in this embodiment, but either or both may be used incombination with this embodiment. Radar 710 (or ultrasonic transceiveror a combination of an ultrasonic transmitter and ultrasonic receiver)measure a distance to the ground. The distance to the ground provides aride quality for the trench closing assembly 250. Actuator 256 can beadjusted to change the position of trench closing assembly 250 or thedownforce applied to trench closing assembly 250 to achieve a selectedposition for the trench closing assembly 250. Changes in the position oftrench closing assembly 250 may result from changes to the depth oftrench opening assembly 220.

While illustrated with a planter row unit 200, any of the abovedescribed embodiments can be used with an air seeder (not shown), whichalso has a seed trench opening assembly and closing assembly.

Various embodiments of the invention have been described above forpurposes of illustrating the details thereof and to enable one ofordinary skill in the art to make and use the invention. The details andfeatures of the disclosed embodiments are not intended to be limiting,as many variations and modifications will be readily apparent to thoseof skill in the art.

The invention claimed is:
 1. A row unit downforce system comprising: a.a row unit comprising opening discs; b. a downforce actuator inoperational communication with the row unit and constructed and arrangedto apply supplemental downforce to the row unit and opening discs; c. anappurtenance connected to the row unit and disposed between the openingdiscs; d. a monitoring system comprising at least one furrow depthsensor constructed and arranged to generate furrow depth values, whereinthe at least one furrow depth sensor is disposed on the appurtenance;and e. control system module, wherein the control system module isconstructed and arranged to generate actuator command signals inresponse to the furrow depth values.
 2. The row unit downforce system ofclaim 1, further comprising a gauge wheel load sensor in operationalcommunication with the control system module.
 3. The row unit downforcesystem of claim 2, further comprising a downforce control system inoperational communication with the control system module and constructedand arranged to generate actuator command signals for transmission andoperation of the downforce actuator.
 4. The row unit downforce system ofclaim 3, wherein the downforce control system comprises at least onecontrol selected from the group consisting of aproportional-integral-derivative control, a machine learning control, apredictive model control and a lookup table.
 5. The row unit downforcesystem of claim 3, wherein the downforce control system utilizes gaugewheel load and furrow depth to modify applied downforce.
 6. A row unitdownforce system comprising: a. a row unit comprising opening discs; b.a downforce actuator in operational communication with the row unit andconstructed and arranged to apply supplemental downforce to the row unitand opening discs; c. an appurtenance connected to the row unit anddisposed between the opening discs; and d. an on-the-go monitoringsystem comprising at least one furrow depth sensor constructed andarranged to generate furrow depth values, wherein the at least onefurrow depth sensor is disposed on the appurtenance.
 7. The row unitdownforce system of claim 6, comprising a gauge wheel load sensorconstructed and arranged to generate gauge wheel load values.
 8. The rowunit downforce system of claim 7, comprising a feedback control systemand a control system module, wherein the control system module isconstructed and arranged to generate actuator command signals inresponse to furrow depth values and gauge wheel load values.
 9. The rowunit downforce system of claim 6, wherein the at least one furrow depthsensor is disposed on an appurtenance.
 10. A row unit downforce systemcomprising: a. a row unit comprising opening discs; b. a downforceactuator in operational communication with the row unit and constructedand arranged to apply supplemental downforce to the row unit and openingdiscs; c. a monitoring system comprising at least one furrow depthsensor constructed and arranged to generate furrow depth values; and d.a control system module, wherein the control system module isconstructed and arranged to generate actuator command signals inresponse to the furrow depth values; wherein the at least one furrowdepth sensor includes a first sensor configured to measure a distancebetween the first sensor and a ground surface and a second sensorconfigured to measure a distance between the second sensor and a targetobject, wherein the first sensor and the second sensor are disposed onthe row unit, and wherein the difference between the distances measuredby the first sensor and the second sensor is a furrow depth value.